Division of' Vibrating Bodies. 209 



and others parallel to that dimension. Several examples of 

 this are shown in Fig. 19, 20, 21, 22, 23, and 24. We may 

 here remark, that the character of the successive modifications 

 depends here, as in membranes, on the manner in which the 

 disunion is effected at the intersection of the lines which at 

 first cut one another. 



It would appear then, that thin and narrow bodies, and even 

 strings, may, like plates and membranes, affect an infinity of 

 modes of division, which transform themselves into one ano- 

 ther by insensible gradations, — for strings are also susceptible 

 of these modes of motion, where there is a longitudinal nodal 

 line cut at right angles by one or more lines of rest ; and we 

 do not see why this mode of division should not pass gradually 

 to that where there are only nodal lines perpendicular to the 

 length. 



From these results we may deduce this general conclusion, 

 that the modes of motion of sounding bodies are much more 

 varied than has hitherto been believed, and that we ought not 

 to admit the existence of determinate series of sounds for each 

 body of a given form, unless with this important restriction, 

 that the proper character of the modes of subdivision ought 

 to remain the same. 



Art. VI. — Contributions to Physical Geography. 



Among the various subjects of popular science, there are few 

 so instructive as those which relate to the physical condition 

 of the globe. The scientific acquirements, and the habits of 

 correct observation which distinguish modern travellers, has 

 enabled them to enrich their works with accurate descriptions of 

 this class of natural phenomena ; but, however interesting they 

 may be, they often escape the notice of scientific readers, and 

 remain buried among the ordinary details of general scenery, 

 or national peculiarities. A collection of such descriptions 

 cannot fail to interest and amuse the general reader, while it 

 furnishes topics of speculation to the physical geographer. 

 Under this impression we shall present our readers with a 

 series of papers on this class of subjects. 



VOL. VI. NO. IT. APRIL 1827- O 



